Here is a job that takes longer than expected (99% of the work throughout this build is done by myself in my home garage, I farm out very little, only some machine work) this needs to be done first, so the cleaning process can remove all the cutting fluid before block fill
I marked the tap at the depth of the cylinder wall
checked it with a gauge plug
and of course, its not deep enough, so I will tap all the holes and then cut the bottom of the tap off to finish the job
